In this work, we compare pressures that can incentivise conciseness during communication emergence. As our testbed, we use a cooperative multi-step navigation task with two RL agents. In the task, a speaker provides navigation hints to help a listener reach a goal within a gridworld maze. We explore three training regimes:
(i) unsituated communication (cheap talk); the speaker sends a message to the listener at each timestep without any cost, similar to the communication paradigm in existing work [1]}, [2]}, [3]},
(ii) unsituated communication with a per-message penalty; the speaker experiences a cost on communication effort (either fixed or progressively increasing), similar to prior work [4]} when fixed,
(iii) situated communication as introduced by Wagner et al. (2003); the listener has to forgo an action to solicit information from the advising agent, experiencing an opportunity cost on communication.
Using the collaborative navigation task, we evaluate how the different pressures in the three training regimes can incentivise sparse information sharing during communication emergence. We find that situated communication (regime iii) outperforms an internal cost on communication effort (regime ii) in terms of both conciseness of the emerged communication protocol and overall task performance.
